Jim - Might you be referring to the Phenix Reds? I looked under that spelling, thinking that they may have been from Phenix City in Russell County. However, as far as I can tell no companies of the 20th came from Russell County. I did find reference to the Phenix Reds in the below history of Selma. It would appear that they may have been, or may have been partially formed from, a fire company. Co. B of the 20th was partially drawn from men from Dallas County. If your browser will allow a "find" for individual words, type "Phenix" in the search field and you will find references to Phenix Fire Co. and Phenix Reds. One reference is to a drill held in March 1861 and another to the city purchasing tents for the company.

https://archive.org/stream/selmaherinstitut00hard/selmaherinstitut00hard_djvu.txt